Home Forums Hunting & Shooting Custom Rifles & Wildcats 7mm Valkyrie AR Project.

In 2013 Harrison Beene ar AR Performance introduced a cat for the AR-15 called the 270AR. Its based on a shorted 308 family case necked down to the 277 in order to fit in a AR-15. Performance is pretty good with a 130gr bullet going a around 2800fps from a 20in barrel. Last fall a few of us started chatting about the same concept but in a 7mm. Bruce Finnegan took the lead and a bunch of us jumped in and funded the reamers and other tooling he needed to make the cat a reality. At first we were discussing just necking up the 270AR to 7mm but it soon was aparent that the shoulder needed pushed back a bit more to allow for the longer bullets. Bruce now has a 24in AR and a 26in bolt and one of the early testers has a 16in AR and a 20in on the way. The rest of us have about 12 in all have a variety of barrel lengths ready to get reamed once the reamers are available to the smith.

The bolts and barrel extenstions used are from ARP what they call the 800 series bolt. It fits a normal AR-15 carrier and made for the 308 case head. Its pretty beefy with rounded lugs and can stand pressures up to 60K. Bruce has a pressure trace system and calling top loads at 57k to leave a margin of safety.

Leverevoution powder is the key enabler and was designed for max velocity from smaller cases and its no surprise its the top performer matching 7mm08 factory loadings. We are getting 2830fps from a 140gr Nosler BT. He got some 160gr Federal Fusion bullets from Rocky Mountain Reloading which aren't normally available as a reloading bullet. I called federal and they confirmed a BC of .528. Max velocity is 2660fps which is a 57K but the accuracy nodes seem to be at 2600fps and 2550fps from a 24in barrel.

The cartridge OAL is 2.295 to fit in a AR-15 magazine we are using 6.8SPC PRI mags which seem to work best. About 7 rounds will fit in a 10 round PRI mag. The mag limitations do limit some bullet selections i have put together a spreadsheet of the bullets that will work about 50 bullets so far which covers from 100gr all the way up to 168gr. Basically the bullets with longer nose cones probably won't work in the AR-15.

When using leverevolution factory 7mm08 performance is possible so this AR cat will be large game capable including Elk and Moose. If your interested in our community project you can read on this thread on msrhunt.com and or the 7mm Valkyrie AR Facebook Group if your on facebook. The cat is not for everyone of course the preferred parent brass is 6.5X47 Lapua which is easiest to form but does require neck turning. The new Hornady Lock N Load neck turning tool has made that part easy. I have a 270AR and messed around with the Forster lathe and recently got the Hornady lathe and its way better. Neck turning is now a breeze. We kind of expect this to stay a small enthusiast cartridge not everyone wants a higher performance AR-15 for hunting but thats ok. its a cartridge we wanted.